
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the
engine is overheating, severe engine damage
may occur. If an overheat warning appears
on the instrument panel cluster and/or
DIC, stop the vehicle as soon as possible.
SeeEngine Overheating on page 460for
more information.
This message displays and a chime sounds
if the engine cooling system reaches unsafe
temperatures for operation. Stop and turn off the
vehicle as soon as it is safe to do so to avoid
severe damage. This message clears when the
engine has cooled to a safe operating temperature.
ENGINE POWER IS REDUCED
This message displays and a chime sounds
when the cooling system temperature gets too
hot and the engine further enters the engine
coolant protection mode. SeeEngine Overheating
on page 460for further information.
This message also displays when the vehicle’s
engine power is reduced. Reduced engine power
can affect the vehicle’s ability to accelerate.If this message is on, but there is no reduction
in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven. The vehicle may be driven
at a reduced speed while this message is on,
but acceleration and speed may be reduced.
Anytime this message stays on, the vehicle
should be taken to your dealer for service as
soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if
the fuel level is low. Refuel as soon as possible.
SeeFuel Gage on page 256andFuel on page 435
for more information.
HOOD OPEN
This message displays and a chime sounds if
the hood is not fully closed. Stop and turn off the
vehicle, check the hood for obstructions, and
close the hood again. Check to see if the message
still appears on the DIC.
270

Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary,
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly
conditions).
You may also want to activate the tow/haul mode
if the transmission shifts too often. See “Tow/Haul
Mode” earlier in this section.
When towing at high altitude on steep uphill
grades, consider the following: Engine coolant
at higher altitudes will boil at a lower temperature
than at or near sea level. If you turn your
engine off immediately after towing at high
altitude on steep uphill grades, your vehicle
may show signs similar to engine overheating.To avoid this, let the engine run while parked
(preferably on level ground) with the automatic
transmission in PARK (P) for a few minutes before
turning the engine off. If you do get the overheat
warning, seeEngine Overheating on page 460.
Parking on Hills
{CAUTION:
You really should not park your
vehicle, with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured,
and both your vehicle and the trailer
can be damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
424

The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 460.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
458

Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the surge tank,
but only when the engine is cool. SeeCooling
System on page 464.
{CAUTION:
You can be burned if you spill coolant
on hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not
spill coolant on a hot engine.
When replacing the pressure cap, make sure
it is hand-tight and fully seated.
Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 444for more
information on location.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 249.
In addition, you will nd an ENGINE
OVERHEATED STOP ENGINE, ENGINE
OVERHEATED IDLE ENGINE, and an ENGINE
POWER IS REDUCED message in the Driver
Information Center (DIC) on the instrument panel.
SeeDIC Warnings and Messages on page 267.
460